The Met Office has upgraded its weather warning for Monday, advising people to "be aware" of severe weather after snow made its first fall in Scotland.

People in parts of Scotland including Peebles saw snow, while a blizzard closed the Kirkstone pass in the Lake District after the conditions were deemed too hazardous for drivers.

Wintery conditions were reported in Salford and Wigan later on Sunday and more sleet and snow was expected for north-west England on Monday.

The RAC is expecting up to 56,000 breakdowns and widespread disruption and has placed extra patrols on standby to help stranded motorists.

Temperatures as low as -10C in Scotland could leave icy roads in Edinburgh, Aberdeen and Glasgow. Eastern England and south-east England were also expected to be hit by snow, which is likely to persist until later in the week.

In London, Heathrow said it had no plans to cancel flights despite weekend warnings that it would halt some as a precaution. The London mayor, Boris Johnson, had claimed it would be "defeatist" to act in advance of bad weather.

He told the Mail on Sunday: "Every time there is a slight problem, Heathrow cannot cope … the answer is not a third runway, but another hub airport for London and the south-east."

A Heathrow spokesman said: "The latest forecast is for a light snowfall at Heathrow early on Monday. There are no plans to cancel flights in advance but passengers should allow extra time for their journeys and check with their airline before travelling to the airport."

Since 2010, the airport has spent £36m on its "winter resilience programme", which included the purchase of 69 extra vehicles and pieces of snow clearing equipment.